Abstract: A load self-leveling system for a vehicle utilizing hydraulic cylinders to operate a telescopic lifting boom and a material handling carriage. The system includes a pair of fluid flow dividers interposed between the source of hydraulic fluid under pressure and the hydraulic cylinders operating the boom and carriage. The flow dividers are structured to direct a greater flow of hydraulic fluid to the boom cylinder and a lesser flow to the carriage cylinder, the precise numeric proportions of flow division being engineered to best suit a particular vehicle, combined with the specific componentry of that vehicle. In addition to the flow dividers, the system includes reversible flow piloted check valves, override control including override relief valves to allow independent adjustments, and matched cylinder area ratios. A compact assembly housing various of the components comprising the system is disclosed.

Abstract: A sensing system for a load carrying vehicle having a hydraulically controlled load carrier which is subjected to cantilever loading such that tipping of the vehicle may occur. The vehicle includes a load bearing frame and an axle supporting that frame. The frame is mounted through a sub-frame assembly so as to be separable to a limited degree from the axle. The initiation of this separation signals the dangerous load condition. A load sensing device disposed between the axle and the sub-frame assembly detects the initiation of separation of the sub-frame from the axle. The sensor functions as a mechanically actuated relief valve in the hydraulic system by which cantilever loading is accomplished. Flow of hydraulic fluid from the sensing device functions to prevent further extension of the load which could induce tipping. Details of the sub-frame assembly and sensing device are disclosed.